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Impedance Spectroscopy (IS) is a general term for the technique referring to small-signal measurements of the linear electrical response of a domain of interest. This method is based on the analysis of the system's electrical response to yield helpful information about its domain-dependent physicochemical properties (generally, the analysis is carried out in the frequency domain). Nowadays, there are many areas of application where IS can be used to evaluate or enhance the development of emerging products and processes. As a contribution to this field of research, this paper presents relevant theoretical–practical aspects of the interpretation and analysis of the electrical behavior of materials based on IS and IS modelling. The work starts by historically introducing IS and then goes through different domains of application of the technique, such as Materials Science and correlated areas. Afterwards, an introduction to IS usage for constructing equivalent electrical circuits is presented, aiming at modelling the materials' electrical behavior, followed by examples from the literature that use the two possible circuit development approaches, the series and the parallel association of circuit elements. Lastly, the authors present a case study of their most recent efforts of a circuit model development of relative humidity (RH) sensors based on heterogeneous mixed metal oxide (MMO) nanostructures, used to understand and identify existing contributions to the overall electrical response of the sensors to moisture; in their case, the electrical response of the MMO sensors was modelled with a high level of superposition between the experimental and fitted data, using a parallel combination of circuit elements, which is an unconventional one. [ABSTRACT FROM AUTHOR]

Proton conductors are ceramic materials with a crystalline or amorphous structure, which allow the passage of an electrical current through them exclusively by the movement of protons: H+. Recent developments in proton-conducting ceramics present considerable promise for obtaining economic and sustainable energy conversion and storage devices, electrolysis cells, gas purification, and sensing applications. So, proton-conducting ceramics that combine sensitivity, stability, and the ability to operate at low temperatures are particularly attractive. In this article, the authors start by presenting a brief historical resume of proton conductors and by exploring their properties, such as structure and microstructure, and their correlation with conductivity. A perspective regarding applications of these materials on low-temperature energy-related devices, electrochemical and moisture sensors, is presented. Finally, the authors' efforts on the usage of a proton-conducting ceramic, polyantimonic acid (PAA), to develop humidity sensors, are looked into. [ABSTRACT FROM AUTHOR]

Climate change and associated shifts in temperature and precipitation patterns have become an increasing concern as drivers of ongoing biodiversity loss. The Mediterranean region is particularly vulnerable, being both a biodiversity hotspot and a region very prone to desertification. Freshwater mussels are amongst the most threatened invertebrate taxa worldwide. Unio tumidiformis is an endemic and endangered species restricted to the southern Iberian Peninsula, living in temporary Mediterranean-type streams. Freshwater mussels need a fish host for successful larval transformation, meaning U. tumidiformis must belong to the genus Squalius. The main objective of this study was to evaluate the vulnerability of U. tumidiformis to climate change, by studying its population genetics and evolutionary history, its current and future habitat suitability, and that of its hosts. Genetic population structure and diversity were assessed using Single-Nucleotide Polymorphisms through Genotyping by Sequencing and used to infer species evolutionary history. The species potential distribution was modeled using an ensemble forecasting approach, and future shifts in habitat suitability were assessed with the projected climate data layers from Worldclim. Most populations showed extreme genetic differentiation (Fst up to 0.745), even from close neighboring ones. Upper Guadiana populations were more diverse and less differentiated. We hypothesize that U. tumidiformis originated in Upper Guadiana and followed the same colonization routes as their hosts with numerous founder effects and bottlenecks. Our results also predicted a reduction of 99% of climatically suitable areas for U. tumidiformis in the Iberian Peninsula until 2040. For the fish hosts, a maximum 42% reduction in suitable areas was estimated throughout the century, with remaining adequate habitats in the north. Our results suggest that difficult conservation options are necessary, prioritizing the preservation of populations, translocations to the northern area of its historical range and stream engineering to increase resilience to droughts. [ABSTRACT FROM AUTHOR]

Tier-2 reading fluency interventions are specifically tailored for struggling readers, addressing their unique needs. The aim of this study was to examine the impact of a Tier-2 reading fluency intervention on reading capabilities and motivation among third-grade students identified as at risk. The intervention employed various strategies, including non-repetitive reading, exploration of challenging words, model reading, eco-reading, assisted reading, and both self- and hetero-assessment of reading proficiency. A two-group randomized controlled trial was employed, comprising an intervention group (N n = 162) and a delayed intervention control group (N = 183). Both groups underwent pre-test and post-test evaluations in reading accuracy and fluency. Additionally, a separate cohort of students without reading difficulties was assessed (N = 225). The intervention resulted in significantly improved word reading accuracy and reading fluency scores in the intervention group compared to the control group. While the gap between the intervention and control groups was slightly reduced, no significant effects on motivation were observed. These findings underscore the relevance of Tier-2 reading fluency interventions in preventing the development of persistent reading difficulties. [ABSTRACT FROM AUTHOR]

Humidity sensors are of huge importance in diverse domains. Several types of materials present a moisture-sensing capacity; however, frequently, their electrical response does not display time stability. Due to its high thermal stability, high ionic conductivity, and different conduction mechanism contributing to its overall conductivity, polyantimonic acid (PAA) is seen as a promising material for humidity-sensing devices. In the present work, crystalline PAA was obtained via a simple and safe hydrolysis technique using SbCl3 as a precursor. Bulky sensor samples were produced using different amounts of polyvinyl alcohol (10–20 wt.% PVA) as a binder. The obtained PAA solid sensors were tested at room temperature (RT) in order to evaluate their moisture detection/measuring ability in the relative humidity range 0–100%; the evaluation was carried out with electrical impedance spectroscopy. The sample's structure and morphology were studied using diverse experimental techniques (porosimetry, scanning electron microscopy, X-ray diffraction analysis, and thermogravimetry analysis, etc.). The sensors' electrical response was in line with the found structural and morphological features. The slope of the resistance variation with an RH percentage concentration between 1 kΩ and 1.5 kΩ was noted for all sensors (showing no changes with time) in the interval between 30 and 100% RH. A good repeatability and reproducibility of the evaluated sensors' electrical response was observed: the ones that displayed a higher sensitivity were the ones with a high PVA binder content, higher than previously published results for PAA, as well as a very good time stability along the time and low hysteresis. [ABSTRACT FROM AUTHOR]

It is important to identify children who are struggling with emergent literacy skills as early as possible to provide them with the support they need to prevent future academic failure. Screening tools administered in groups are more cost-effective than those administered individually, but few are available in Portugal. The goal of this study was to explore the psychometric properties (difficulty, reliability, and validity) of a group emergent literacy screening test for Portuguese-speaking children. The test includes two phonological awareness tasks, one vocabulary task, and one concepts of print task. The sample comprised 1379 children from pre-K (n = 314), kindergarten (n = 579), and first grade of primary education (n = 486). Measures of emergent literacy, reading and writing skills, and academic achievement were used to test the validity of the screening test. The Rasch model results suggest that the tasks were suitably difficult for the kindergarten group, but had varying levels of difficulty for pre-K and first grade. Reliability was adequate for the tasks with an appropriate level of difficulty. Scores for the screening test were highly correlated with measures of literacy and with academic achievement. These findings suggest that the presented emergent literacy screening test is valid and reliable, making it a useful tool for practice and research. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide and carbon monoxide share the ability to be beneficial or harmful molecules depending on the concentrations to which organisms are exposed. Interestingly, humans and some bacteria produce small amounts of these compounds. Since several publications have summarized the recent knowledge of its effects in humans, here we have chosen to focus on the role of H2S and CO on microbial physiology. We briefly review the current knowledge on how bacteria produce and use H2S and CO. We address their potential antimicrobial properties when used at higher concentrations, and describe how microbial systems detect and survive toxic levels of H2S and CO. Finally, we highlight their antimicrobial properties against human pathogens when endogenously produced by the host and when released by external chemical donors. [ABSTRACT FROM AUTHOR]

High sodium (salt) consumption is associated with an increased risk of developing non-communicable diseases. However, in most European countries, Portugal included, sodium intake is still high. This study aimed to assess the sodium content of school meals before and after the Eat Mediterranean (EM) intervention—a community-based program to identify and correct nutritional deviations through the implementation of new school menus and through schools' food handlers training. EM (2015–2017) was developed in 25 schools (pre to secondary education) of two Portuguese Municipalities, reaching students aged 3–21 years old. Samples of the complete meals (soup + main course + bread) from all schools were collected, and nutritional quality and laboratory analysis were performed to determine their nutritional composition, including sodium content. Overall, there was a significant decrease (−23%) in the mean sodium content of the complete school meals, which was mainly achieved by the significant reduction of 34% of sodium content per serving portion of soup. In conclusion, EM had a positive effect on the improvement of the school meals' sodium content, among the participant schools. Furthermore, school setting might be ideal for nutrition literacy interventions among children, for flavors shaping, and for educating towards less salty food acceptance. [ABSTRACT FROM AUTHOR]